Supramolecular columns of hexabenzocoronenes on copper and gold (111) surfaces

Abstract
We report on the growth of supramolecular columns of polyaromatic hydrocarbons on Au(111) and Cu(111) single-crystal surfaces. The lateral separation of the columns was found to depend on the substrate and is determined by the commensurately formed superlattice of the first molecular monolayer. X-ray photoelectron diffraction in combination with low-energy electron diffraction reveals stack growth with small lateral offsets from the column axis but with conservation of the molecular orientation. The mechanism of column growth is explained by simulation results of the intermolecular interaction assuming a Lennard-Jones potential. The size of hexabenzocoronene and its ability to condense into one-dimensional supramolecular structures make it an ideal candidate for the accommodation and the positioning of functional groups to form a functional molecular assembly.